president Obama is trying to reassure Americans about the threat from Isis. One of our close it allies great Britain has raised its terror threat level so should we follow suit? Could Isis hit us at home? Straight to the white house and ABC's Jeff Zeleny, good morning to you, Jeff. Reporter: Good morning, Dan. You're right the president is trying to strike that balance between warning and reassuring Americans. As his team is still weighing how to confront the rising threat of islamic extremism hitting closer to home. Strong comments from president Obama about the threat from the militant islamic group Isis. Speaking to supporters on Friday, he says the world has always been messy, but images on social media of beheadings, mass executions and attacks have only heightened our fears and the president saying we will get through these challenges times just like we have in the past. The president's words coming just as the United Kingdom raised its terror level threat to fear. A risk of an attack is highly likely. We're facing a deeper threat to our security than we have known before. Reporter: No changes in U.S. Warnings. This morning, there are rising concerns about homegrown American recruits to Isis. We've seen where some individuals start to branch out and travel to other hot spots around the globe, obviously Syria being one of them. Reporter: Even though the FBI and department of homeland security say they're unaware of any specific credible threat. Online music videos like this one from an American rapper. This goes out to all my soldiers ? A popular way to recruit -- They slaughter us like animals now it's final for that beast to bottom. Syria to Atlanta. Recruiting friends and friends of friends. Reporter: Back in Washington president Obama and his advisers are weighing their options, not threatening or ruling out military strikes like this one. I don't want to put the cart before the horse. We don't have a strategy yet. Reporter: But it's those six words from the president, we don't have a strategy yet that still is causing him political grief. Republicans say he's indecisive but white house officials say he's simply trying to send the message he's not rushing into another war.

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